I've been in Tarquinia in the year 2000 and I've got there
by bus from Rome. In Tarquinia you should visit not only the
museum, but also the cemetery site with great Etruscan
frescoes inside some of the tombs. The views from there are
also gorgeous.

The trip to Tarquinia can be best combined by a visit of
nice Cervetery. The cemetery site is more interesting,
though the frescoes are not really preserved.